feat(agent): budget reminders, usage while waiting, budget-exceeded status and dedupe

- tool results carry a budget reminder near limits; text before the last tool
  call is dropped as report when cut by budget/abort
- usage persisted when a run suspends, so waiting sessions show spent tokens
- task page shows budget_exceeded via business.outcome instead of completed
- budget-exceeded decisions merge by root cause (decision / schedule / goal
  template); new summaries added to investigate allowlist

Co-Authored-By: Claude Opus 5.5 <[email protected]>

apps/web/app/components/tasks/task-stream.tsx

@@ -18,8 +18,8 @@ import {
   BUSINESS_KINDS,
   businessLink,
   ENGINE_ACTIVE,
+  engineRunStatus,
   RUN_STATUS_OPTIONS,
-  runStatus,
   runTitle,
   SOURCE_LABEL,
   SOURCE_TRIGGERED_BY,
@@ -247,7 +247,7 @@ export function TaskStream({
             key: "status",
             header: "状态",
             cell: (r) => {
-              const s = runStatus(r.status);
+              const s = engineRunStatus(r);
               return <StatusBadge tone={s.tone}>{s.label}</StatusBadge>;
             },
           },